Drilling and production method



19-66 R. D. JOHNSTONE ETAL DRILLING AND PRODUCTION METHOD 4 Sheets-Sheet1 Original Filed July 10, 1961 ROBERT D. JOHNSTONE & CHARLES E.WAKEFIELfiEgJRw INVENTO AT TORNEY.

Dec. 13, 1966 R. D. JOHNSTONE ETAL DRILLING AND PRODUCTION METHODOriginal Filed July 10, 1961 4 Sheets-Sheet 2 ROBERT D. JOHNSTONE &G'MRLES EWAKEFIELDJRH INVENTORS ATTORNEY.

196 R. D. JOHNSTONE ETAL L DRILLING AND PRODUCTION METHOD Original FiledJuly 10, 1961 4 Sheets-Sheet 5 AT TORNEY.

Dec. 13, 1966 R. D. JOHNSTONE ETAL DRILLING AND PRODUCTION METHODOriginal Filed July 10, 1961 l 4 Sheets-Shet 4 ROBERT D. JOHNSTONE &CHARLES EWMKEFI ELDJRJ INVENTORS.

M TRNEY.

over the well bore.

United States Patent Claims. '(Cl. 166-.6)

The present invention is a divisional, application of Serial No.122,918, filed July 10, 1961, and relates to the drilling and productionof petroleum from a formation underlying a body of water and moreparticularly, relates to a method for drilling and subsequentlyproducing petroleum from a formation underlying a relatively deep bodyof water with a minimum use of divers.

When drilling into and producing from a formation containing oil and gasunder high pressure, blowout prevention equipment is conventionally usedin the drilling operation; and a flanged wellhead assembly with atChristmas tree thereon is normally utilized to control the production ofoil and gas from the well during its period of natural flow. In offshoreoperations, the drilling and production apparatus including the drillinghead and the blowout prevention equipment has normally been installed ona marine platform located on the surface of the water Marine productionequipment using a platform constitutes an obstacle to navigation andappearance and is limited to relatively shallow water usage. The priorart production apparatus assembly includes,

generally, a-casing which is normally cemented into the well, a casingspool, a tubing head, a casing head, and the various Christmas treecomponents including a master valve, one or more wing valves, and suchflow constricting devices as may be required in a particular well.

Recently the drilling and production apparatus has been mounted on theocean floor in relatively shallow water accessible to divers. Equipmentused in such shallow water operations is, however, unsuitable for theproduction of oil wells in deeper water due to the need for exten sivediving operations needed to assemble and locate the various wellheadcomponents. Such shallow water equipment requiring the use of diverswould be extremely difiicult to install in deeper water since diver worktime is greatly reduced at greater depths. Fluid controlled wellheadequipment, such as the conventional blowout prevention equipment,necessarily involves the use of fluid hose connections to the wellheadequipment, e.g., the blowout preventer, which hoses frequently are inneed of repair or must replaced which must normally be done When thewellhead is located on the ocean floor, through the use of divers. Wherethe wellhead equipment is located in deeper water the replacement orrepair of these hoses presents a significant problem due to thereduction in diver work time at greater depths.

The prior art techniques also require removal of the drilling mandrel orhead prior to completion of the well and subsequent installation of aproduction head which involves additional use of divers or remoteoperating means.

It is therefore an object of our present invention to produce petroleumfrom wells underlying relatively deep bodies of water and to provide amethod for installing drilling and production equipment from the surfacewith a minimum use of divers.

It is also an object of our present invention to provide a method forusing a combination drilling and production mandrel by remoteinstallation at an underwater formation from the surface of the body ofwater.

It is a further object of our present invention to proice vide a methodfor producing a well drilled into a formation underlying a body ofrelatively deep water without first removing the drilling mandrel.

It is a further object of our present invention to provide a method forproducing a well drilled into a formation underlying a body ofrelatively deep water by utilizing the drilling mandrel as a productionmandrel.

Other objects and a more complete understanding of our present inventionmay be realized by reference to the following specification and claimswhen taken in conjunction with the accompanying drawings, in which:

FIG. 1 is an elevational view, partially in section, showing the mannerin which the drilling of the well bore is started and the drilling baseis lowered to the formation;

FIG. 2 is an elevational view, partially in section, showing anassembled surface casing, production head, blowout preventer, and acasing riser as the assemblage is lowered to the ocean floor;

FIG. 3 shows in elevational partial section, the drilling apparatus ofFIG. 2 landed on the ocean fioor and a water string landed in thedrilling apparatus;

FIG. 4 is an elevational view in partial section showing schematicallythe manner in which the tubing string may be hung within the wellhead;

FIG. 5 is an elevational view in partial section showing schematicallythe manner in which the wellhead is sealed off preparatory to removal ofthe riser pipe and blowout prevention equipment;

FIG. 6 is an elevational view in partial section showing a productionbarge and the wellhead during production after the casing riser andblowout prevention equipment has been removed from the wellhead;

FIG. 7 is an elevational view, partially in section, showing a modifiedproduction arrangement.

With reference to the drawings generally, the wellhead of the parentapplication is shown in FIGS. 2-5, with a sequential showing of how ourwellhead may be installed at the ocean floor. Briefly described, anapparatus is shown which can be remotely installed on the ocean floorand portion thereof raised to the drilling vessel for repairs,replacements or other purposes -by the provision of a modified blowoutpreventer housing 38 having a shoulder 44 formed thereon which houses aremovable control block 48 through which the blowout prevention controlhoses 50 are attached to the blowout preventer, thus enabling thecontrol block 48 with the control hoses 50 to be raised to the drillingvessel (not shown), with the help of a guide arm 58 and sleeve 56slidably attached to the casing riser 36. The completion of the well andinstallation of the production equipment may be accomplished remotelythrough underwater production apparatus, for example, the speciallydesigned drilling and production mandrel 32, the production aspect ofwhich is more fully defined and described in a copending application,Serial No. 100,411, filed April 3, 1961, for Submarine Drilling andProduction Head and Method of Installing Same, in the name of Charles E.Wakefield, Jr. The present method involves utilizing the drillingmandrel 32 as a production mandrel and producing the well through flowlines 64 and 66.

Referring now more particularly to the drawings, FIG. 1 shows a concretedrilling base 10 lowered from a floating vessel (not shown) on loweringcables 12 to the formation 14 beneath the body of water 16. The drillingbase 10 has a conductor pipe 18 extending therethrough. Drill pipe 20has drill bit 22 and a drilling collar 24- attached to the lower endthereof. The base 10 with conductor pipe 18 may be installed at theformation by first extending the lower end of the drill pipe through thelanding base and conductor pipe 18 while the landing base is suspendedover the formation, so that the drill string may be operatedtherethrough from the floating vessel to cut the well bore 26 in theformation. The drill base may then be lowered to the formation with theconductor pipe extending into the well bore 26. A hole opener 28 is usedto enlarge the well bore 26 for conductor pipe 18.

After the well bore has been deepened sufficiently to receive thesurface casing 30, the surface casing 30 is connected to drillingmandrel 32 by any suitable means, e.g., a threaded coupling joint 34,and the casing riser 36 and blowout prevention equipment 38 connected tothe drilling mandrel 32 and the assemblage lowered from the floatingvessel, as shown in FIG. 2, into the drilling base 10 at the formation14, on the riser pipe 36 over the drill pipe which may be left in thewell bore temporarily to provide guidance between the floating vesseland the drilling base for, the wellhead assemblage. Television apparatusof the type described in the copending application of Robert O. Pollardet al., Serial No. 144,- 204, may also be used to guide the lower end ofthe assemblage into the hole. The mandrel 32 is similar to theproduction mandrel described in the aforementioned copending applicationSerial No. 100,411. A conventional remotely disconnectible latch orsafety joint 40 is used to connect the blowout preventer 38 to thedrilling mandrel 32. Thi safety joint is preferably a straight pullsafety joint for releasing the drilling mandrel 32 from the safety joint40 and may employ a latch operated by a cable (not shown), for example,the right hand torque releasing safety joint found on page 4557 of the1958-59 Composite Catalog of Oil Field and Pipeline Equipment, publishedby World Oil. A similar safety joint 42 may be provided at theconnection between the blowout preventer 38 and the casing riser 36 sothat the casing riser can be remotely released above the blowoutpreventer.

The blowout preventer housing 38 has a shoulder portion 44 formedthereon. Thi housing has a manifold section 46 with passageways 45extending internally therethrough and through the shoulder portion 44 asshown in FIG. 2. The passageways preferably extend at one end 47 to theconventional blowout preventer actuating mechanisms which are within theblowout preventer housing 38 to there effect control fluid communicationbetween the hoses 50 and the blowout preventer. The other end 49 of thepassageways 45 form receptacles 51 to receive control hose terminals 53which may have sealing rings thereon (not shown). The control block 48houses the control hose terminals 53 which protrude from the lower sidethereof to connect with the passageways or receptacles 51 in themanifold section 46. The control block 48 has passageways through whichthe control hose terminals pass and receive the fluid control hoses 50from the floating vessel.

The control block 48 is removable from the manifold section 46 and has ahoisting member 52 attached thereto and extending to the floating vesselfor raising and lowering the control block 48 onto the manifold section46 of the blowout preventer shoulder portion 44. The hoisting member 52preferably is a rigid steel member such as a rod or a tubular member.Spacer disc 54 is provided to evenly distribute the control hoses aboutthe hoisting member 52 and prevent entanglements and damage to thehoses. An orientation sleeve 56 having an orientation lug 56a therein isslidably disposed in orientation cam 36a on the casing riser 36 andrigidly attached to the hoisting member 52 by a rod or tubular member 58to aid in guiding the control block 48 as it is lowered and raised toand from the blowout preventer manifold section 46.

A casing outlet 60 and a tubing outlet 62, more fully shown in theabove-mentioned copending application, are connected respectively to thecasing flow line 64 and the tubing flow line 66 either by a diver,remote connecting means, or at the vessel as taught in copendingapplication of C. E. Wakefield, Jr., Serial No. 454,020, filed May 7,1965, for Method for Connecting a Flow Line to an Underwater Well. Fluidoperated valves 68 and 70 control flow between the tubing and easingoutlets and the tubing and casing flow lines respectively, and arecontrolled through fluid control hose 72 which extends to the floatingvessel. The tubing and easing valves 68 and 70 are normally closed. Aplate or landing flange 74 fastened to the drilling mandrel 32 serves asa drilling mandrel landing base and supports the wellhead within thedrilling base until the surface casing and production head are cementedtogether into the formation.

After the surface pipe, production pipe, blowout preventer, and easingriser are concentrically assembled and lowered to the ocean bottom,drilling tools are operated through the assemblage to deepen the wellsufliciently to receive a water string.

As shown in FIG. 3, the water string is next lowered into the well borethrough the riser pipe and the drilling mandrel on the drill string withan appropriate release tool (not shown) onto a suitable casing hanger,e.g. a shoulder provided in the lower end of the drilling head 32, or amodified Burns fluted holddown liner hanger attached to the long end ofthe drilling mandrel 32 which hanger would have the surface casing 30coupled thereto. The water string 76 is supported on the hanger, e.g.shoulder 80, by a water string landing mandrel 78 coupled to the upperend of the water string 76, which mandrel has a shoulder 79 which seatson shoulder 80 of the hanger.

The tubing 82 with a tubing plug 84 is then lowered into the wellthrough the water string and hung within the drilling mandrel 32 on atubing hanger 86 as more fully described in our above-mentionedcopending application. Packer cups 88 and 90 seal around the tubingabove and below the tubing outlet 62 to restrict the tubing flow throughthe tubing outlet and tubing flow line 66, as shown in FIG. 4. Plug 92is fastened into the upper end of the drilling mandrel 32, as shown inFIG. 5, to serve as a secondary seal behind the packer cup 88 and as asafety device against the possibility of blowing the tubing out of thehole.

After the drilling operation is completed and the well brought intoproduction, the casing riser and blowout prevention equipment may beraised to the floating vessel by releasing the safety joint 40, aspreviously described, leaving the drilling mandrel in flow operatingposition as shown in FIG. 6. The flow lines and flow control lines 64,66, and 72, may be run from the wellhead to a production barge 94. Asshown in FIG. 7, a production tank 96 may be submerged and productiontherefrom pumped to a tanker loading buoy 98 or directly to a tanker(not shown) through tanker loading lines 100. In operations near theshore, flow lines 64 and 66 may be run along the ocean floor 14 to aproduction control facility on shore. In such case one of the loweringlines 12 may be used to locate the well with a buoy.

Thus, with the present invention the drilling and production apparatusmay be lowered together as a unit and the drilling mandrel serves as aproduction head since the drilling tools may be operated therethrough.Thus, the blowout preventer referred to herein may be latched to awellhead which may be either a drilling head, a production head, or acombination drilling and production head. During the drilling operationthe blowout preventers which are normally open and only closed whenthere is an unbalanced pressure condition in the well, may be remotelycontrolled from the drilling vessel through fluid control lines 50 whichmay be repaired or replaced by raising the control block 48 to thedrilling vessel by retracting the hoisting cable 52 and the blowoutpreventer control hoses either repaired or replaced as required. Thus,it is not necessary to send a diver down to the wellhead to repair thefluid control hoses at the blowout preventer connections where they mostoften fail' The type of blowout prevention equipment, which isconventional equipment, contemplated for use in the present inventionemploys 3 gates, which are: (1) a complete shutoff gate; (2) a gate forshutting off only around the drill pipe; and (3) a hydril or bag typeblowout preventer on top of the above-mentioned blowout preventer. Afterthe drilling is accomplished to the desired depth, the well may becompleted and brought into production by lowering the production stringthrough the casing riser and blowout preventer into the drilling mandreland mounting the production string within the drilling mandrel as is setforth in the aforementioned copending application drawn to a productionhead per se and the method for installing such production head.

Although the present invention has been described in its preferred formwith a certain degree of particularity, it should be understood thatthis disclosure has been made only by way of example and that numerouschanges in the details of the method and in the combination andarrangements of parts may be made without departing from the spirit andscope of the invention as herein claimed.

We claim:

1. In a method for drilling and completing a well in a formationunderlying a body of water from a vessel floating on said body of waterwherein an apertured landing base is positioned on said formation, thesteps comprising:

(a) operating a drill string in said well from said vessel to drill saidwell sufficiently to receive a surface pipe,

(b) assembling at said vessel, said surface pipe, a drilling andproduction mandrel having a tubing flow line connector, and a blowoutpreventer,

(c) lowering said assemblage into said well through said apertureddrilling base with said mandrel landing adjacent said base,

(d) operating drilling tools through said mandrel to deepen said well,

(e) lowering a water string into said well through said mandrel,

(f) landing said water string,

(g) landing a production tubing string in said mandrel,

(h) operatively connecting said production tubing string to a tubingflow line through said tubing flow line connector of said mandrel,

(i) removing said blowout preventer,

(j) and producing said well through said production string and saidproduction mandrel tubing flow line connector.

2. The method of claim 1 wherein said assemblage is lowered into saidwell through said apertured drilling base over said drill string whilesaid drill string is in said well.

3. The method of claim 1 including the step of plugging said mandrelabove said tubing flow line connector after said tubing string has beenlanded in said mandrel.

4. In a method for drilling and completing a well in a formationunderlying a body of water from a vessel floating on said body of waterwherein an apertured landing base is positioned on said formation, thesteps comprising:

(a) operating a drill string in said well from said vessel to drill saidwell sufliciently to receive a surface pipe,

(b) assembling at said vessel said surface pipe, a drilling andproduction mandrel having a tubing flow 5 line connector, a blowoutpreventer, and a casing riser,

(c) lowering said assemblage into said well through said apertureddrilling base with said mandrel landing adjacent said base,

deepen said well,

(e) lowering a water string into said well through said mandrel,

(f) landing a production tubing string in said mandrel,

(g) operatively connecting said production tubing string to a tubingflow line through said tubing flow line connector of said mandrel, (h)removing said blowout preventer and said riser,

5. In a method for drilling and completing a well in a formationunderlying a body of Water from a vessel floating on said body of waterwherein an apertured landing base is positioned on said formation, thesteps comprising:

(a) operating a drill string in said well from said vessel to drill saidwell sufliciently to receive a surface pipe,

(b) concentrically assembling at said vessel, said surface pipe, adrilling and production mandrel having a tubing flow line connector, ablowout preventer,

and a casing riser,

drel landing adjacent said base,

(d) operating drilling tools through said mandrel,

duction head,

(f) landing a production tubing string in said mandrel,

line connector of said mandrel,

(h) plugging s aid mandrel above said tubing flow line connector,

(i) removing said blowout preventer and said riser,

(j) and producing said well through said production string and saidproduction mandrel tubing fiow line connector.

References Cited by the Examiner UNITED STATES PATENTS CHARLES E.OCONNELL, Primary Examiner.

R. E. FAVREAU, Assistant Examiner.

(d) operating drilling tools through said mandrel to (i) and producingsaid Well through said production string and said production mandreltubing flow line (c) lowering said assemblage into said well throughsaid apertured drilling base over said drill string while said drillstring is in said well with said man- (e) lowering a Water string intosaid well through said mandrel and landing said water string in saidpro- (g) operatively connecting said production tubing string to atubing flow line through said tubing flow

1. IN A METHOD FOR DRILLING AND COMPLETING A WELL IN A FORMATIONUNDERLYING A BODY OF WATER FROM A VESSEL FLOATING ON SAID BODY OF WATERWHEREIN AN APERTURED LANDING BASE IS POSITIONED ON SAID FORMATION, THESTEPS COMPRISING: (A) OPERATING A DRILL STRING IN SAID WELL FROM SAIDVESSEL TO DRILL SAID WELL SUFFICIENTLY TO RECEIVE A SURFACE PIPE, (B)ASSEMBLING AT SAID VESSEL, SAID SURFACE PIPE, A DRILL ING AND PRODUCTIONMANDREL HAVING A TUBING FLOW LINE CONNECTOR, AND BLOWOUT PREVENTER, (C)LOWERING SAID ASSEMBLAGE INTO SAID WELL THROUGH SAID APERTURED DRILLINGBASE WITH SAID MANDREL LANDING ADJACENT SAID BASE,